A disposable diaper whose portion to face a crotch portion of a wearer is folded along groins of the wearer is conventionally proposed. A development type disposable diaper disclosed in Japanese Patent Application Laid-Open No. 2007-222370 (Document 1) has a liquid-pervious top sheet, a water-repellent or liquid-impervious back sheet and an absorbent core located between the both sheets. In a crotch region, the absorbent core has a central core and a pair of leg cores positioned at both sides of the central core. Elastic members are provided at intermediate areas between the central core and the pair of leg cores. In the intermediate areas, portions of the top sheet stand up on a skin contact surface so as to form a pair of water-conducting walls. When the disposable diaper is worn, portions provided with the leg cores are bent downward due to existence of the intermediate areas. In the disposable diaper, the portions are brought into close contact with the insides of thighs of the wearer, and therefore leakage from leg circumferences is improved.
A pants-type disposable diaper disclosed in Japanese Patent Application Laid-Open No. 2004-49709 (Document 2) has a top sheet, a back sheet, an absorbent main body located between the both sheets, and leg flap elastic members extending along leg openings of the diaper. In a crotch region, the leg flap elastic members are positioned between the absorbent main body and the back sheet. In the absorbent main body, on each side portion in a width direction, a leg flap absorbent body, which is bending toward an outer surface by extensional stress of the leg flap elastic member, is formed. When the diaper is worn, the leg flap absorbent bodies are brought into contact with the insides of thighs of the wearer, and therefore excrement which has leaked out from the crotch region is absorbed into the leg flap absorbent bodies.
In a disposable diaper disclosed in Japanese Patent Application Laid-Open No. 2002-209939 (Document 3), strip-like leg absorbent bodies are provided left and right of a central absorbent body, and intermediate areas where no absorbent body is provided or a weight of absorbent body per unit area is low are provided between the central absorbent body and the leg absorbent bodies. In addition, elastic members are fixed between the leg absorbent bodies and a back sheet.
In the diaper of Document 1, since the portions provided with the leg cores are brought into close contact with large areas of leg circumferences of the wearer, they interfere with leg movement of the wearer. The same applies to Documents 2 and 3.